Process of making piston rings



1935- c; E. JOHNSON PROCESSXH MAKI-NG PISTON RINGS Filed May 25, 1931 2Sheets-Sheet 1 M MI! I Jan. 22, 1935. c, JOHNSON 1,988,738

PROCESS OF MAKING PISTON RINGS Filed May 25, 1951 2 Sheets-Sheet 2 1% CL@"IIIIIIIIH 5 A Patented Jan; 22, 1935 1,988,738

1,988,738 noosss or MAKING PISTON mos Charles E. Johnson, NorthMuskegon, Mich. Application May 25, 1931, Serial No. 539,881 3 Claim.(01. 29-min) This invention relates1to piston rings and a Fig. 4 is afragmentary elevation partly in novel method of producing the same.section showing mother manner of treating the The present invention isdirected to a practical ring to carry out the process. and simple pistonring construction and a very Fig. 5 is a fragmentary enlarged partialper- 5 practical, efilcient, simple and economical proc--. spective andsection through the ring, illue- 5 es of treating the ring castings toproduce trating indentations made in the opposite paralthe finishedring, and provide the requisite tenlei fiat sides of the ring and fromthe inner sion in the completed piston ring so that, with curved side ofthering outward to provide an an expanding ring seated in a piston ringexpanding piston ring.

1o groove within a cylinder, the outer curved sur- Fig. 6 is a viewsimilar to Fig. 1 showing the m faceot the ring bears snuglyand withsumcient plstonringtobetreatedforthe production of a pressure againstthe inner walls of the cylinder; contractiiigipiston ring, utilizing thesame procwhile with a contracting ring seated in a groove ess. in thewall of a cylinder around a reciprocating Pig. 7 is an elevationillustrating the complete s piston or piston rod the inner curved sideof the contracting ring after it has been subjected to ring bears snuglyagainst the outer cylindrical the process of my invention, and surfaceof the piston or piston rod, whereby in Fig. 8 is a view similar to Fig.3 illustrating both cases an'eflective seal is made between the themechanism for rrying out the process on! piston and the cylinder or rodto obviate the indenting the ring at its opposite parallel flat soescape of compression on the passage of oil or sides and at the outercurved portion of the ring gases of combustion or between the pisandextending inwardly therefrom, for the proton and cylinder or between apistonrod and its ductionof a contracting ring. I V packing ring. I Likereference characters refer to like parts,

Piston rings of the so-cailed hammered type in the different figures ofthe drawings. as are hardtoproducein'the matter of uniformity The pistonring casting 1 is of circular formin rings and also uniformity in thecircumi'erenand is finished at its opposite fiat sides and attits. tiallength or a ring which is necessary for the outer curved side in themanufacture for an" production of a good quality piston ring. Theexpanding ring with a parting at one side as process of hammering ringsrequires large and indicated at 2. The inner curved side of the soexpensive equipment particularly because of the ring may be finished butit is not ry Q very many diiferent sizes of piston rings which in myinvention as theseale of the casting mayare standard and are called forby the makers be left on which'strengthens the ring and also I and usersof internal combustion and other enreduces the cost of manufacture. Igines, pumps and the like. The present inven- In carrying out my novelprocess where an extion produces not only piston rings which are pendingring is to be produced, both the upper 35 01' uniform quality throughoutbut the process and lower fiat parallel sides of the ring are ma becarried out economically with very simpref ably ind nt d at i sysnceed-anart in-, pie machinery and with great rapidity. tervals, asindicated at 3, from the inner curved An understanding of the inventionfor the side or the ring outward toward the outer so attainment of theends stated may be had from curvedside or the upper and lower dg m y sothe following description, taken. in connection rolled with a smoothroller obtaining the same UNITED STATES PATENT-OFFICE- with theaccompanying drawings, in which, esults; the indentation or rolling a ngd ep-1:

Fig.1 isan elevationofapistonringpriortoestattheinnersideoftheringandrunnliigout@ thccompletion of the processfor making an and ending betore reaching the outer curved expanding ringwherein normally, when free to side, as best shown in Figs. 8 and 5. Inpro- 3 do so, the ends. of the finished ring at the partviding theseindentations the same are made ing are separated from each other by a.condeepest directly opposite the ring gap and pro-. siderable gap.gressively decrease in depth and length toward Fig. 21s a like elevationshowing the ring of the gap or parting so that adjacent said parting 60Fig. 1 after it has been subjected to the process the indentations runout and disappear as of my invention. shown in Fig. 2. v Fig. 3 is anelevation, partly in section, show- The indenting and upsetting of themetal by ing the manner in which the ring illustrated the production ofthe indentations 8 as described i in Fig. 1 may be treated to completethe same presses the metal inward at the inner side of IItoprodueethepistonringshcwninligz. theringand causestheringtoexpandwith'a piston rin which 2 deforming of th's circular ringshown in Fig. 1 to an out-of-round form. thereby widening and openingthe parting at 2 is make an appreciably wide gap as indicated at e inFig. 2; and the extent of the gap width at d is dependent upon the depth.and number of the indentations 3 made, the gap being narrower with theshallower indentations and wider with the deeper indentations.

In Fig. 3 asimple means of treating the rings to provide theindentations at its opposite fiat sides and adjacent to its inner curvedside is shown. The table 5 is a table of a well known machine namely;the table of a rotating chuck or anvil which may be driven or rotated atnominal speed. The ring is placed on the anvil and in practice may belocated around or within a slightly raised circular proiwtion having theproper exterior or interior diameter that the ring will fit. Anindenting rotatable tool 1 whereby with the rotation of the ring and theaccompanying rotation of the tool the indentations 3 or it rolled edgeat one side of the ring are almost instantly producedn 4 It is of courseto be understood that one side of the rotating table or anvil isslightly higher than the other so when the ring is revolved under theindenting be deeper opposite the parting and disappear for a shortdistance where the parting is to be made, the axes of rotation of thetable and of the indentingtoolcarelocatedatanangletoeach other. when oneside treated it is turned over. anvil and the opposite sideInFig.4ahandmethodisdisclosedof carrying out the process for theproduction of the consists merely in the use of a hammer '1 and-apeening tool 8 which illustrates the pinning process instead of rolling,stamping onto dies in a press or indenting by means of a drop hammer.

In Figs. 6 to 8 inclusive the process for proplaced'on the table ortreated in the same curved surface the scale may be left thereon whilethe ring is finished at its opposite flat parallel sides and at itsinner curved surface. This ring, placed upon the anvil or table 5, isacted upon by an indenting rotatable tool so to provide the indentationsin or is rolled at its opposite flat parallel sides leading from theouter inner side sai inner side. In the table 5 and the tool 6a rotateare at an angle to each other slightly less than a right angle for theprovision of the deepest indentation directly opposite the parting withtheir progressive decrease in size toward the gap until theydisappear,orthlsisalsoattainedbythetableor tool 6 the indentations willoftheringhasbeenthus' and sides from one anvil being slightlv higher onthe other, the indentations so being in posite flat sides of the ring asshown Theringthusmadehasitsendsattbeparting brought together and theends tightly against each other with considerable pressure in accordancewith the amount of tension force which has by the upsetting indentationor rollin process described; and if the two ends at. the parting weresprung sideways apart from each other the same would pass by each otherfor a distance.

In the manufacture of rings in accordance with this process the ringsare not disturbed, opposite flat sides of the ring are recessed by theindentations 8 or 30, but the metal is not upset outwardly beyond theflat planes of the flat butanupsetinallcasesinthe unfinished scale sideof the ring. The invention described is of a very practical naturepermitting the production of piston rings with quantity productionmachinery and methods and with the provision in an expand-=ingringofaswideagapasmaybedesiredas illustrated at '4 in Fig. 2. andwith ccmparatively light expense in the matter of production carryingout the process.

, the a p nd claims and is to be considered comprehensive of all formsof structure coming within their scope.

I claim: I 1. The method of manufacturing a piston ring one whichconsists in casting the ring, cutting the same at one place, machiningits op osed flat sides to form substantially parallel finished surfaces,and then indenting one of the said parcurved side thereo! and toward itsother curved side whereby small reservoirs are provided for theretention of oil, said indentations terminating short of said othercurved side of the ring.

beendevelopodinthcrina' 2. The process of completing a piston ring,

which consists in machinins the upper and lower faces thereof, thenindenting both opposed flat sides thereof at a plurality of spaced apartpoints with the indentations of from one curved side of the ring towardbut short of the other curved side of the ring whereby small reservoirsare providedfor the retention of oil, the indentations opposite the rinparting and creasing in size from each side thereof toward the rimparting.

3. The process of manufacturing a ring of the class described whichconsists in finishing the upper and lower surfaces thereof. revolvingthe ring about an axis slightly inclined with respect to a plane passingmedially between the upper and lower surfaces of the ring, and indentingthe ring during this wobbling movement whereby small reservoirs of aprogressively varying depth are provided for the retention of oil.

CgARLES E. JOHNSON.

Varyin depth having greatest size

